<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>姓名案例_计算属性实现</title>
    <script type="text/javascript" src="../js/vue.js"></script>
</head>
<body>
    <div id="root">
        姓：<input type="text" v-model="firstName"><br><br>
        名：<input type="text" v-model="lastName"><br><br>
        全名：<span>{{fullName}}</span>
    </div>
</body>
<script type="text/javascript">
    Vue.config.productionTip=false;
    const vm=new Vue({
        el:'#root',
        data:{
            firstName:'小',
            lastName:'慧'
        },
        computed: {
            fullName:{
                //get:当有人读取fullName时，get就会被调用，且返回值就被作为fullName的值
                //get调用：1.初次读取fullName时，2.所依赖的数据发生变化时
                get(){
                   // console.log('get被调用了');
                    return this.firstName+'-'+this.lastName
                },
                //set调用：当fullName被修改的时候
                set(value){
                    console.log('set',value)
                    const arr=value.split('-')
                    this.firstName=arr[0]
                    this.lastName=arr[1]
                }
            }
        }
    })
</script>
</html>